From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:41772) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gjNfw-0007eY-05 for qemu-devel@nongnu.org; Tue, 15 Jan 2019 07:18:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gjNfu-0003Et-Ow for qemu-devel@nongnu.org; Tue, 15 Jan 2019 07:18:35 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:53476) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gjNft-0003Cu-U5 for qemu-devel@nongnu.org; Tue, 15 Jan 2019 07:18:34 -0500 From: Liam Merwick Date: Tue, 15 Jan 2019 12:18:02 +0000 Message-Id: <1547554687-12687-1-git-send-email-liam.merwick@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v3 0/4] QEMU changes to do PVH boot List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: pbonzini@redhat.com, ehabkost@redhat.com, rth@twiddle.net, xen-devel@lists.xenproject.org, sgarzare@redhat.com, mst@redhat.com, stefanha@redhat.com, maran.wilson@oracle.com, george.kennedy@oracle.com, boris.ostrovsky@oracle.com, liam.merwick@oracle.com For certain applications it is desirable to rapidly boot a KVM virtual machine. In cases where legacy hardware and software support within the guest is not needed, QEMU should be able to boot directly into the uncompressed Linux kernel binary with minimal firmware involvement. There already exists an ABI to allow this for Xen PVH guests and the ABI is supported by Linux and FreeBSD: https://xenbits.xen.org/docs/unstable/misc/pvh.html Details on the Linux changes (in 4.21): https://lkml.org/lkml/2018/12/14/= 1330 qboot pull request integrated: https://github.com/bonzini/qboot/pull/17=20 This patch series provides QEMU support to read the ELF header of an uncompressed kernel binary and get the 32-bit PVH kernel entry point from an ELF Note. In load_linux() a call is made to load_elfboot() so see if the header matches that of an uncompressed kernel binary (ELF) and if so, loads the binary and determines the kernel entry address from an ELF Note in the binary. Then qboot does futher initialisation of the guest (e820, etc.) and jumps to the kernel entry address and boots the guest. changes v1 -> v2 - Based on feedback from Stefan Hajnoczi - The reading of the PVH entry point is now done in a single pass during elf_load() which results in Patch2 in v1 being split into Patches 1&2 i= n v2 and considerably reworked. - Patch1 adds a new optional function pointer to parse the ELF note type (the type is passed in via the existing translate_opaque arg - the function already had 11 args so I didn't want to add more than one new = arg). - Patch2 adds a function to elf_ops.h to find an ELF note matching a specific type=20 - Patch3 just has a line added to the commit message to state that the Xe= n repo is the canonical location - Patch4 (that does the PVH boot) is mainly equivalent to Patch3 in v1 just minor load_elfboot() changes and the addition of a read_pvh_start_addr() helper function for load_elf() changes v2 -> v3 - Based on feedback from Stefan Hajnoczi - Fix formatting issues where a few tabs snuck in v2 - Moved code to use ELF Note in load_elf() from Patch1 to Patch2 - In load_elf() set data to NULL after g_free() [now in Patch2 following = move] - Added Patch5 containing changes by Stefano Garzarella to support -initr= d Us=D1=96ng the method/scripts documented by the NEMU team at https://github.com/intel/nemu/wiki/Measuring-Boot-Latency https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg00200.html below are some timings measured (vmlinux and bzImage from the same build) Time to get to kernel start is almost halved (95=E1=B9=81s -> 48ms) QEMU + qboot + vmlinux (PVH + 4.20-rc4) qemu_init_end: 41.550521 fw_start: 41.667139 (+0.116618) fw_do_boot: 47.448495 (+5.781356) linux_startup_64: 47.720785 (+0.27229) linux_start_kernel: 48.399541 (+0.678756) linux_start_user: 296.952056 (+248.552515) QEMU + qboot + bzImage: qemu_init_end: 29.209276 fw_start: 29.317342 (+0.108066) linux_start_boot: 36.679362 (+7.36202) linux_startup_64: 94.531349 (+57.851987) linux_start_kernel: 94.900913 (+0.369564) linux_start_user: 401.060971 (+306.160058) QEMU + bzImage: qemu_init_end: 30.424430 linux_startup_64: 893.770334 (+863.345904) linux_start_kernel: 894.17049 (+0.400156) linux_start_user: 1208.679768 (+314.509278) Liam Merwick (4): elf: Add optional function ptr to load_elf() to parse ELF notes elf-ops.h: Add get_elf_note_type() pvh: Add x86/HVM direct boot ABI header file pvh: Boot uncompressed kernel using direct boot ABI hw/alpha/dp264.c | 4 +- hw/arm/armv7m.c | 3 +- hw/arm/boot.c | 2 +- hw/core/generic-loader.c | 2 +- hw/core/loader.c | 24 ++++--- hw/cris/boot.c | 3 +- hw/hppa/machine.c | 6 +- hw/i386/multiboot.c | 2 +- hw/i386/pc.c | 135 +++++++++++++++++++++++++++++++++++= ++ hw/lm32/lm32_boards.c | 6 +- hw/lm32/milkymist.c | 3 +- hw/m68k/an5206.c | 2 +- hw/m68k/mcf5208.c | 2 +- hw/microblaze/boot.c | 7 +- hw/mips/mips_fulong2e.c | 5 +- hw/mips/mips_malta.c | 5 +- hw/mips/mips_mipssim.c | 5 +- hw/mips/mips_r4k.c | 5 +- hw/moxie/moxiesim.c | 2 +- hw/nios2/boot.c | 7 +- hw/openrisc/openrisc_sim.c | 2 +- hw/pci-host/prep.c | 2 +- hw/ppc/e500.c | 3 +- hw/ppc/mac_newworld.c | 5 +- hw/ppc/mac_oldworld.c | 5 +- hw/ppc/ppc440_bamboo.c | 2 +- hw/ppc/sam460ex.c | 3 +- hw/ppc/spapr.c | 7 +- hw/ppc/virtex_ml507.c | 2 +- hw/riscv/sifive_e.c | 2 +- hw/riscv/sifive_u.c | 2 +- hw/riscv/spike.c | 2 +- hw/riscv/virt.c | 2 +- hw/s390x/ipl.c | 9 ++- hw/sparc/leon3.c | 3 +- hw/sparc/sun4m.c | 6 +- hw/sparc64/sun4u.c | 4 +- hw/tricore/tricore_testboard.c | 2 +- hw/xtensa/sim.c | 12 ++-- hw/xtensa/xtfpga.c | 2 +- include/elf.h | 10 +++ include/hw/elf_ops.h | 77 ++++++++++++++++++++++ include/hw/loader.h | 9 ++- include/hw/xen/start_info.h | 146 +++++++++++++++++++++++++++++++++++= ++++++ 44 files changed, 479 insertions(+), 70 deletions(-) create mode 100644 include/hw/xen/start_info.h --=20 1.8.3.1